Instead Of a battery it is powered by a little solar panel on the watch facial area (the 'Eco Push') and because of 'Atomic Timekeeping' it may possibly claim for being the 'most accurate watch on the earth'. A. Lange & Söhne's watches are an embodiment of heritage and craftsmanship, https://www.watchesworld.com/germanys-top-10-favourite-luxury-watches/